1. Field of the Invention
This invention relates to a multi-packaging device for unitizing and carrying a plurality of containers wherein distinct physical characteristics are present along adjacent strips of material within a plastic sheet.
2. Description of the Prior Art
Multi-packaging devices, such as the device according to this invention, are used to unitize a plurality of containers. Typically, containers include bottles, cans and other containers having a sidewall and a chime or raised rib around an upper portion of the container. Much of the prior art in this area, specifically multi-packaging devices constructed from elastic, polymeric materials, comprises multi-packaging devices that engage the chime or rib around the upper portion of the container. Another style of multi-packaging device is the sidewall applied carrier wherein the multi-packaging device engages the sidewall of the container.
Regardless of the style of multi-packaging device, one challenge in the art is to provide a multi-packaging device that can be used with a range of container sizes, specifically a range of container diameters. Because the container engaging portions of the multi-packaging device are generally elastic, which is governed by the modulus of elasticity or xe2x80x9cmodulusxe2x80x9d of the multi-packaging device, the multi-packaging device relies upon the engagement of a stretched container engaging portion with the container sidewall or chime. Container diameters outside of a narrow range of diameters will either stretch the container engaging portion too much thereby permanently losing elasticity, called xe2x80x9cneck-down,xe2x80x9d or not stretch the container engaging portion at all, both scenarios resulting in package failure.
Prior art multi-packaging devices generally require several different versions or configurations to accommodate different diameters of containers. Typically, a single design multi-packaging device can accommodate a range of container diameters of 0.200 inches. It is therefore desirable to provide a multi-packaging device that can accommodate an increased range of container diameters.
In addition, prior art multi-packaging devices do not permit the flexibility of introducing various physical properties into the composition of the multi-packaging device so as to permit use in a wide variety of applications.
It is one object of this invention to provide a multi-packaging device that permits the flexibility of introducing various physical properties into the composition of the multi-packaging device so as to permit use in a wide variety of applications.
It is another object of this invention to provide a multi-packaging device that unitizes a plurality of containers into a package that resists movement of the containers relative to each other.
It is another object of this invention to provide a device that unitizes a plurality of containers having a first diameter, which device is also capable of unitizing a plurality of containers having a second diameter.
It is a further object of this invention to provide a device that may be used in a wide range of applications thus obviating production of many different devices of varying size and shape.
It is still another object of this invention to provide a device that is positioned around the sidewall of a container when a sidewall diameter is within an approximately one inch range of diameters.
A multi-packaging device capable of accommodating a range of container diameters is preferably constructed from a thermoplastic material, such as a plastic sheet. A resilient polymer having a lower modulus than the plastic sheet is preferably integrated with the plastic sheet. The resilient polymer preferably forms discrete segments within the plastic sheet so that the multi-packaging device comprises a single, generally linear thickness.
According to another preferred embodiment of this invention, the multi-packaging device may comprise the plastic sheet having a generally uniform thickness and alternating and discrete strips of different materials extending parallel with respect to the array of apertures, wherein each strip of the alternating and discrete strips of plastic sheet includes at least one distinct physical property from each adjacent strip. Preferably, the plastic sheet is coextruded to create a generally uniform thickness that includes alternating and discrete strips of different materials positioned side-by-side and in registry with respect to one another. The distinct physical properties in the adjacent strips of different materials may include any one or more of two different moduli, two different coefficients of friction, two different colors or two different recycled material contents.
The plastic sheet having the integrated resilient polymer is next preferably die-cut to form a plurality of apertures, each aperture capable of receiving a container. The apertures are preferably arranged in an array of lateral rows and longitudinal ranks and formed so that the resilient polymer is adjoining the plastic sheet in one of several preferred locations and/or the adjacent strips of materials are formed in desired locations. In one preferred embodiment of this invention, the resilient polymer is positioned in discrete segments within the plastic sheet and between the apertures in the lateral rows of apertures. In another preferred embodiment of the invention, the resilient polymer or discrete strip of different material is positioned along outer bands in the lateral rows of apertures adjacent to the plastic sheet so that an adjacent strip of material within the plastic sheet is contained in the inner bands of the lateral rows of apertures. In still another preferred embodiment of the invention, the resilient polymer or discrete strip of different material is positioned within the plastic sheet between the apertures in the lateral rows of apertures and contiguous with at least a portion of the perforations.
A container is then inserted into each aperture to form an assembled multi-packaging device and, depending upon the diameter of the container, the plastic sheet and/or the resilient polymer will stretch accordingly. Alternatively or in addition, a portion of the plastic sheet will grip according to its respective coefficient of friction. Additionally, a portion of the plastic sheet may contain a different recycled material content or a different color from that portion in an adjacent strip of different material within the plastic sheet.